U.S. patent application number 13/701416 was filed with the patent office on 2013-06-13 for method for cultivating plant and plant cultivation device.
This patent application is currently assigned to OSAKA UNIVERSITY. The applicant listed for this patent is Fumiteru Akamatsu, Hiroshi Fuji, Kazuhito Fujiyama, Kazuo Harada, Jun Hayashi, Kazumasa Hirata, Satoru Kato, Akio Kobayashi, Shuji Kurimoto, Takashi Machimura, Atsushi Okazawa, Yoshito Suda, Naoyuki Tatsumi. Invention is credited to Fumiteru Akamatsu, Hiroshi Fuji, Kazuhito Fujiyama, Kazuo Harada, Jun Hayashi, Kazumasa Hirata, Satoru Kato, Akio Kobayashi, Shuji Kurimoto, Takashi Machimura, Atsushi Okazawa, Yoshito Suda, Naoyuki Tatsumi.
Application Number | 20130145688 13/701416 |
Document ID | / |
Family ID | 45066526 |
Filed Date | 2013-06-13 |
United States Patent
Application |
20130145688 |
Kind Code |
A1 |
Tatsumi; Naoyuki ; et
al. |
June 13, 2013 |
METHOD FOR CULTIVATING PLANT AND PLANT CULTIVATION DEVICE
Abstract
A plant cultivation method of the present invention includes the
steps of: placing a plant under a condition at a pressure of not
less than 1.5 atmospheres and not more than 10 atmospheres; and
cultivating the plant. A plant cultivation device (1) includes: a
cultivation chamber (10); and a compressor (20) which supplies
compressed air into the cultivation chamber. A carry-in opening
(30), which is provided on a side wall (16) of the cultivation
chamber (10) so that a material is carried in/out to/from the
cultivation chamber (10) via the carry-in opening (30), is provided
with a cover (31) which has a shape that is hemispherical and
protrudes toward an inside of the cultivation chamber (10). The
cover (31) closes the carry-in opening (30) by being in contact,
via a packing (32), with an inner surface of the side wall (16)
surrounding the carry-in opening (30). The cultivation chamber (10)
has an internal pressure higher than an atmospheric pressure by
causing the compressor (20) to supply compressed air into the
cultivation chamber (10) in a state in which the carry-in opening
(30) is closed. A plant growth rate is improved by cultivating a
plant in a high pressure environment which is different from a
natural environment. A plant cultivation device is provided for
achieving plant cultivation in a high pressure environment.
Inventors: |
Tatsumi; Naoyuki;
(Osaka-shi, JP) ; Fuji; Hiroshi; (Osaka-shi,
JP) ; Akamatsu; Fumiteru; (Suita-shi, JP) ;
Kobayashi; Akio; (Suita-shi, JP) ; Kurimoto;
Shuji; (Suita-shi, JP) ; Suda; Yoshito;
(Suita-shi, JP) ; Fujiyama; Kazuhito; (Suita-shi,
JP) ; Okazawa; Atsushi; (Suita-shi, JP) ;
Hirata; Kazumasa; (Suita-shi, JP) ; Harada;
Kazuo; (Suita-shi, JP) ; Machimura; Takashi;
(Suita-shi, JP) ; Kato; Satoru; (Suita-shi,
JP) ; Hayashi; Jun; (Suita-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Tatsumi; Naoyuki
Fuji; Hiroshi
Akamatsu; Fumiteru
Kobayashi; Akio
Kurimoto; Shuji
Suda; Yoshito
Fujiyama; Kazuhito
Okazawa; Atsushi
Hirata; Kazumasa
Harada; Kazuo
Machimura; Takashi
Kato; Satoru
Hayashi; Jun |
Osaka-shi
Osaka-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi
Suita-shi |
|
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP |
|
|
Assignee: |
OSAKA UNIVERSITY
Suita-shi, Osaka
JP
SHARP KABUSHIKI KAISHA
Osaka-shi, Osaka
JP
|
Family ID: |
45066526 |
Appl. No.: |
13/701416 |
Filed: |
April 19, 2011 |
PCT Filed: |
April 19, 2011 |
PCT NO: |
PCT/JP2011/059649 |
371 Date: |
January 29, 2013 |
Current U.S.
Class: |
47/60 ;
47/58.1R |
Current CPC
Class: |
Y02A 40/264 20180101;
A01G 7/00 20130101; A01G 9/24 20130101; Y02A 40/25 20180101; A01G
9/00 20130101 |
Class at
Publication: |
47/60 ;
47/58.1R |
International
Class: |
A01G 9/00 20060101
A01G009/00; A01G 1/00 20060101 A01G001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 4, 2010 |
JP |
2010-128958 |
Claims
1. A plant cultivation method comprising the steps of: placing a
plant under a condition at a pressure of not less than 1.5
atmospheres and not more than 10 atmospheres; and cultivating the
plant.
2. The plant cultivation method as set forth in claim 1, wherein
the plant is placed under a condition at a pressure of not less
than 1.5 atmospheres and not more than 4 atmospheres.
3. A plant cultivation device comprising: a cultivation chamber in
which plant cultivation is carried out; a compressor which supplies
compressed air into the cultivation chamber; a carry-in opening
which is provided on a wall of the cultivation chamber and via
which a material is carried in/out to/from the cultivation chamber;
and a cover which is provided to the carry-in opening and has a
shape that protrudes toward an inside of the cultivation chamber,
the cover closing the carry-in opening by being in contact with a
surface of the wall surrounding the carry-in opening, the surface
being located on the cultivation chamber side, and the cultivation
chamber having an internal pressure higher than an atmospheric
pressure by causing the compressor to supply compressed air into
the cultivation chamber in a state in which the carry-in opening is
closed.
4. The plant cultivation device as set forth in claim 3, wherein
the shape of the cover is hemispherical.
5. The plant cultivation device as set forth in claim 3, further
comprising: a hinge which is provided to the surface of the wall of
the cultivation chamber, the surface being located on the
cultivation chamber side, the cover being connected via the hinge
to the wall of the cultivation chamber.
6. The plant cultivation device as set forth in claim 5, further
comprising: a first connecting member which is provided on an outer
surface of the cover; and a second connecting member which is
provided on the wall of the cultivation chamber, the first
connecting member and the second connecting member engaging with
each other in a state in which the carry-in opening is closed with
the cover.
7. The plant cultivation device as set forth in claim 3, further
comprising: a packing which is provided between the cover and the
wall of the cultivation chamber, the carry-in opening being closed
in a state in which the packing is sandwiched between the cover and
the wall surrounding the carry-in opening.
8. The plant cultivation device as set forth in claim 3, further
comprising: an inlet/outlet which is provided to the cover, the
compressor supplying compressed air into the cultivation chamber
via the inlet/outlet.
9. A plant cultivation method for carrying out cultivation by use
of a plant cultivation device recited in claim 3, said method
comprising the steps of: placing a plant under a condition at a
pressure which is higher than an atmospheric pressure; and
cultivating the plant.
10. The plant cultivation method as set forth in claim 9, wherein
the plant is placed under a condition at a pressure of not less
than 1.5 atmospheres and not more than 4 atmospheres.
11. The plant cultivation method for carrying out plant cultivation
in a cultivation chamber for plant cultivation, the cultivation
chamber being a sealed space in which a plant is placed, said
method comprising the step of: cultivating the plant by causing a
pressure device to increase an internal pressure of the cultivation
chamber so that the internal pressure is higher than an atmospheric
pressure.
12. The plant cultivation device as set forth in claim 4, further
comprising: a hinge which is provided to the surface of the wall of
the cultivation chamber, the surface being located on the
cultivation chamber side, the cover being connected via the hinge
to the wall of the cultivation chamber.
13. The plant cultivation device as set forth in claim 4, further
comprising: a packing which is provided between the cover and the
wall of the cultivation chamber, the carry-in opening being closed
in a state in which the packing is sandwiched between the cover and
the wall surrounding the carry-in opening.
14. The plant cultivation device as set forth in claim 5, further
comprising: a packing which is provided between the cover and the
wall of the cultivation chamber, the carry-in opening being closed
in a state in which the packing is sandwiched between the cover and
the wall surrounding the carry-in opening.
15. The plant cultivation device as set forth in claim 6, further
comprising: a packing which is provided between the cover and the
wall of the cultivation chamber, the carry-in opening being closed
in a state in which the packing is sandwiched between the cover and
the wall surrounding the carry-in opening.
16. The plant cultivation device as set forth in claim 4, further
comprising: an inlet/outlet which is provided to the cover, the
compressor supplying compressed air into the cultivation chamber
via the inlet/outlet.
17. The plant cultivation device as set forth in claim 5, further
comprising: an inlet/outlet which is provided to the cover, the
compressor supplying compressed air into the cultivation chamber
via the inlet/outlet.
18. The plant cultivation device as set forth in claim 6, further
comprising: an inlet/outlet which is provided to the cover, the
compressor supplying compressed air into the cultivation chamber
via the inlet/outlet.
19. The plant cultivation device as set forth in claim 7, further
comprising: an inlet/outlet which is provided to the cover, the
compressor supplying compressed air into the cultivation chamber
via the inlet/outlet.
20. A plant cultivation method for carrying out cultivation by use
of a plant cultivation device recited in claim 4, said method
comprising the steps of: placing a plant under a condition at a
pressure which is higher than an atmospheric pressure; and
cultivating the plant.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for plant
cultivation in a high pressure environment, and a plant cultivation
device which is used to cultivate a plant in a high pressure
environment.
BACKGROUND ART
[0002] A food market, especially a fresh vegetable market has been
growing in size, whereas problems have been growing evident.
Examples of the problems include climate change, a decline in
employed agricultural population, aging of farmers, a decrease in
food self-sufficiency rate, disguise of production regions. This
causes a matter of concern about food safety and security.
[0003] Such circumstances have been raising more expectations for a
so-called plant factory so as to (i) supply chemical-free
vegetables, (ii) improve traceability of products such as
vegetables, (iii) achieve stable production and supply, and (iv)
increase a food self-sufficiency rate. A plant factory refers to a
facility for cultivating a plant in an enclosed and
environmentally-controlled space. Japan is currently making efforts
at a widespread use of plant factories as its national policy in
view of, for example, an increase in food self-sufficiency rate,
safety, and an advanced use of land.
[0004] In order to develop a plant factory, it is significant to,
for example, (i) control various parameters related to plant growth
such as a light intensity and a temperature, (ii) create an optimum
environment for plant growth, (iii) shorten a cultivation period,
and (iv) increase an yield. For example, a research has been
carried out concerning which wavelength of light, out of
wavelengths of light to be emitted from a light source, contributes
to plant growth.
[0005] FIG. 10 shows a relationship between a type of LED light, or
a ratio between red LED (R) light and blue (B) LED light, and a
plant growth rate. FIG. 10 is data posted on a web site of Plant
Factory Laboratory (refer to Nonpatent Literature 1). Referring to
a result shown in this drawing, it is possible to create a lighting
environment suitable for plant growth.
[0006] Patent Literature 1 discloses a minute pressure control
device for controlling a pressure in an enclosed space for plant
cultivation or the like to be slightly different from an outdoor
air pressure. FIG. 11 shows an arrangement of a stationary pressure
control device which is disclosed in Patent Literature 1.
[0007] The pressure control device shown in FIG. 11 includes an air
buffer 101 which is provided on a floor surface 132 of an airtight
container 102. The air buffer 101 is made of an elastic material
such as rubber and has a hollow rectangular shape. A duct 109 is
connected to the air buffer 101, and the duct 109 communicates, via
a valve 103, with a duct 107, which is connected to a closed module
(not illustrated) to be controlled.
[0008] A duct 111 is connected to the duct 109 and exposed to
atmospheric air via a valve 104. Meanwhile, the airtight container
102 is provided with a duct 112 which is exposed to atmospheric air
via a valve 106, and a duct 110 which is connected to the duct 107
via a duct 105.
[0009] The pressure control device shown in FIG. 11 and having the
arrangement is capable of controlling a pressure in the closed
module to be minute and positive or negative with respect to an
outdoor air pressure. For example, in order to control the pressure
in the closed module to be positive, the pressure control device
closes the valve 104 and the valve 105, whereas the pressure
control device opens the valve 103 and the valve 106. Accordingly,
since the valve 106 is open, atmospheric pressure is drawn into the
airtight container 102 via the duct 112. In this case, an internal
pressure of the air buffer 101 is equal to a pressure obtained by
adding an internal pressure (atmospheric pressure) of the airtight
container 102 and an empty weight of a film member of the air
buffer 101. This causes the pressure in the closed module to be
minute and positive with respect to the atmospheric pressure. Since
the valve 103 is open, an inside of the air buffer 101 communicates
with the closed module via the duct 109. Therefore, the pressure in
the closed module is controlled to be minute and positive as in the
case of the internal pressure of the air buffer 101.
CITATION LIST
Patent Literature
[0010] Patent Literature 1
[0011] Japanese Patent Application Publication, Tokukaihei, No.
11-334789 (Publication Date: Dec. 7, 1999)
Nonpatent Literature
[0012] Nonpatent Literature 1
[0013] "Handoutai kougen ni yoru seichou-ritsu (Growth rate
measured by use of semiconductor light source)", online, Search
Date: May 12, 2010, URL <http://www.sasrc.jp/seicho.htm>
SUMMARY OF INVENTION
Technical Problem
[0014] Artificial lighting using an LED and a minute pressure
control using a pressure control device serve as examples of a
natural environment imitated in a facility. Namely, a conventional
plant factory intends to cause an environment in a facility to
resemble a natural environment as much as possible.
[0015] On the contrary, hardly any attempt has been made to
cultivate a plant in an environment which is significantly
different from a natural environment. In particular, no knowledge
has been acquired about a growth state in a high pressure
environment which is impossible in a natural environment.
[0016] In view of the circumstances, an object of the present
invention is to (i) improve a plant growth rate by cultivating a
plant in a high pressure environment which is different from a
natural environment and (ii) provide a plant cultivation device for
achieving plant cultivation in such a high pressure
environment.
Solution to Problem
[0017] In order to attain the object, a plant cultivation method in
accordance with the present invention includes the steps of:
placing a plant under a condition at a pressure of not less than
1.5 atmospheres and not more than 10 atmospheres; and cultivating
the plant.
[0018] The method enables further promotion of plant growth as
compared to a method of cultivating a plant at a normal pressure
(approximately 1 atmosphere).
[0019] In order to attain the object, a plant cultivation device in
accordance with the present invention includes: a cultivation
chamber in which plant cultivation is carried out; a compressor
which supplies compressed air into the cultivation chamber; a
carry-in opening which is provided on a wall of the cultivation
chamber and via which a material is carried in/out to/from the
cultivation chamber; and a cover which is provided to the carry-in
opening and has a shape that protrudes toward an inside of the
cultivation chamber, the cover closing the carry-in opening by
being in contact with a surface of the wall surrounding the
carry-in opening, the surface being located on the cultivation
chamber side, and the cultivation chamber having an internal
pressure higher than an atmospheric pressure by causing the
compressor to supply compressed air into the cultivation chamber in
a state in which the carry-in opening is closed.
[0020] A plant cultivation device of the present invention includes
a cultivation chamber and a compressor which supplies compressed
air into the cultivation chamber. The plant cultivation device
causes the cultivation chamber to have an internal pressure higher
than an atmospheric pressure by causing the compressor to supply
compressed air in a state in which a carry-in opening provided to
the cultivation chamber is closed with a cover.
[0021] According to such a plant cultivation device, the cover
provided to the carry-in opening closes the carry-in opening by
being in contact with a surface (i.e., an inner surface) of a wall
surrounding the carry-in opening, the surface being located on the
cultivation chamber side. In other words, the cover is arranged to
cover the carry-in opening from the inside of the cultivation
chamber.
[0022] Note here that, in a case where the internal pressure of the
cultivation chamber is increased by supplying compressed air into
the cultivation chamber from the compressor, an internal and
external pressure difference causes a force toward an outside of
the cultivation chamber to be applied to the cover. According to
the arrangement in which the cover covers the side wall surrounding
the carry-in opening from the inside of the cultivation chamber,
the force is applied to the cover in a direction in which the cover
is adhered to a side wall of the cultivation chamber. Thus, the
arrangement enables an improvement in sealing property of the
cultivation chamber. Further, the arrangement prevents the cover
from coming off also in a case where the internal pressure of the
cultivation chamber rises. This allows a vicinity of the carry-in
opening to be more resistant to pressure.
[0023] In addition, the cover which has a shape that protrudes
toward the inside of the cultivation chamber allows an increase in
surface area of the cover. According to this, a large force which
is caused by the internal pressure of the cultivation chamber is
applied, toward the outside of the cultivation chamber, to a
surface of the cover which surface faces the cultivation chamber.
Thus, the arrangement allows a further improvement in sealing
property in accordance with an increase in internal pressure of the
cultivation chamber.
[0024] As described earlier, the plant cultivation device of the
present invention makes it possible to cultivate a plant while
maintaining an internal pressure of the cultivation chamber so that
the internal pressure is higher than an atmospheric pressure.
[0025] In order to attain the object, the plant cultivation method
in accordance with the present invention is a method for carrying
out plant cultivation in a cultivation chamber for plant
cultivation, the cultivation chamber being a sealed space in which
a plant is placed, the method including the step of: cultivating
the plant by causing a pressure device to increase an internal
pressure of the cultivation chamber so that the internal pressure
is higher than an atmospheric pressure.
[0026] The method allows further promotion of plant growth as
compared to a plant cultivation method carried out at an
atmospheric pressure (approximately 1 atmosphere).
Advantageous Effects of Invention
[0027] A plant cultivation method in accordance with the present
invention includes the steps of: placing a plant under a condition
at a pressure of not less than 1.5 atmospheres and not more than 10
atmospheres; and cultivating the plant. The method enables further
promotion of plant growth as compared to a method of cultivating a
plant at a normal pressure (approximately 1 atmosphere).
[0028] A plant cultivation device in accordance with the present
invention includes: a cultivation chamber in which plant
cultivation is carried out; a compressor which supplies compressed
air into the cultivation chamber; a carry-in opening which is
provided on a wall of the cultivation chamber and via which a
material is carried in/out to/from the cultivation chamber; and a
cover which is provided to the carry-in opening and has a shape
that protrudes toward an inside of the cultivation chamber, the
cover closing the carry-in opening by being in contact with a
surface of the wall surrounding the carry-in opening, the surface
being located on the cultivation chamber side, and the cultivation
chamber having an internal pressure higher than an atmospheric
pressure by causing the compressor to supply compressed air into
the cultivation chamber in a state in which the carry-in opening is
closed.
[0029] The plant cultivation method in accordance with the present
invention is a method for carrying out plant cultivation in a
cultivation chamber for plant cultivation, the cultivation chamber
being a sealed space in which a plant is placed, the method
including the step of: cultivating the plant by causing a pressure
device to increase an internal pressure of the cultivation chamber
so that the internal pressure is higher than an atmospheric
pressure.
[0030] This makes it possible to yield an effect of cultivating a
plant while maintaining an internal pressure of the cultivation
chamber so that the internal pressure is higher than an atmospheric
pressure.
BRIEF DESCRIPTION OF DRAWINGS
[0031] FIG. 1 schematically shows an arrangement of a plant
cultivation device in accordance with an embodiment of the present
invention.
[0032] FIG. 2 is an exploded view schematically showing components
of a sealed structure of a carry-in opening of the plant
cultivation device shown in FIG. 1.
[0033] FIG. 3 schematically shows how to close the carry-in opening
with a cover which is provided to a side wall of a cultivation
chamber of the plant cultivation device shown in
[0034] FIG. 4 schematically shows an arrangement of a plant
cultivation device used in an example of the present invention.
[0035] FIG. 5 shows an external appearance of the plant cultivation
device used in the example of the present invention.
[0036] FIG. 6 shows a result of the example of the present
invention.
[0037] FIG. 7 is a graph showing a result of the example of the
present invention.
[0038] FIG. 8 schematically shows an arrangement of a plant
cultivation device in accordance with a second embodiment of the
present invention.
[0039] FIG. 9 schematically shows an arrangement of a cover
provided to a carry-in opening of the plant cultivation device
shown in FIG. 8.
[0040] FIG. 10 is a graph showing a relationship between a type of
LED light or a ratio between LED lights of respective colors, and a
plant growth rate.
[0041] FIG. 11 schematically shows an arrangement of a conventional
pressure control device used for pressure control of a plant
cultivation chamber.
DESCRIPTION OF EMBODIMENTS
[0042] Inventors of the present invention conducted an experiment
of cultivating a plant in a high pressure environment which is
impossible in a natural environment. As a result, the inventors
accomplished the present invention by finding that a plant growth
rate is higher in a high pressure environment than in an
environment at a normal atmospheric pressure.
[0043] The following embodiments specifically describe arrangement
examples of a plant cultivation facility and preferable cultivation
conditions. Note that, unless otherwise specified, sizes,
materials, shapes, relative positions, and the like of components
described in each of the following embodiments do not intend to
limit the scope of the present invention but merely serve as
examples for explanation.
Embodiment 1
[0044] An embodiment of the present invention is described below
with reference to FIG. 1 to FIG. 7.
[0045] First, the present embodiment discusses an arrangement of a
plant cultivation device for achieving plant cultivation in a high
pressure environment.
[0046] FIG. 1 shows an arrangement of a plant cultivation device 1
in accordance with an embodiment of the invention. The plant
cultivation device 1 includes a cultivation chamber 10 of a closed
system and an oil-free compressor 20 for causing an inside of the
cultivation chamber 10 to be a high pressure environment (see FIG.
1).
[0047] An oil-free compressor 20 is connected, via a pipe 21, to an
inlet/outlet 11 which is provided on a side wall 16 of the
cultivation chamber 10. This makes it possible to supply compressed
air to the cultivation chamber 10. A commonly used compressor can
be used as the oil-free compressor 20, and a compressor to be used
is not limited to an oil-free compressor.
[0048] The cultivation chamber 10 is large and wide enough for a
man to enter an inside thereof for carrying out operation. The
cultivation chamber 10 mainly includes a lighting apparatus 12
which is resistant to pressure, a temperature and humidity sensor
13, a nutrient solution supplying device 14, and a temperature and
humidity control device 15.
[0049] The side wall 16 of the cultivation chamber 10 is provided
with a carry-in opening 30 in addition to the inlet/outlet 11. A
material is carried in/out from/to the cultivation chamber 10 via
the carry-in opening 30. The carry-in opening 30 is closed by a
sealed structure for creating a high pressure environment inside
the cultivation chamber 10. A specific arrangement of the sealed
structure is described later.
[0050] The cultivation chamber 10 is not provided with no opening
to an outside for ventilation other than the carry-in opening 30
having the sealed structure and the inlet/outlet 11 connected to
the oil-free compressor 20 (a compressor, a pressure device).
Namely, a part of the cultivation chamber 10 which part is obtained
by excluding the carry-in opening 30 and the inlet/outlet 11 is a
completely sealed space.
[0051] The lighting apparatus 12 includes a light source which is
resistant to a high pressure environment having a pressure of
approximately not more than 10 atmospheres. The light source is
exemplified by an LED (a light emitting diode), a fluorescent lamp,
a metal halide lamp, and a high pressure sodium lamp. However, the
light source is not particularly limited to these provided that the
light source is resistant to a high pressure environment.
[0052] The temperature and humidity sensor 13 is connected to the
temperature and humidity control device 15 which is provided
outside or inside of the cultivation chamber 10. The temperature
and humidity control device 15 is provided with an operation panel
serving as a setting section for setting a temperature and a
humidity of the cultivation chamber 10.
[0053] The temperature humidity control device 15 can be made by
use of a general-purpose air conditioner which allows heat exchange
in a state in which a space between the cultivation chamber 10 and
an outside of the temperature humidity control device 15 is sealed.
In accordance with information about the temperature and the
humidity of the cultivation chamber 10, the information having been
acquired by the temperature and humidity sensor 13, the temperature
humidity control device 15 also maintains the temperature and the
humidity of the cultivation chamber 10 which have been set.
[0054] Note that the operation panel may be replaced with a remote
operation terminal such as a remote control or an information
processing terminal (e.g., a personal computer). It is also
possible to provide a humidifier in the cultivation chamber 10. It
is preferable that the temperature and humidity control device 15
be resistant to a high pressure environment having a pressure of
approximately not more than 10 atmospheres.
[0055] The nutrient solution supplying device 14 includes a tray in
which plants 40 are provided and a culture solution tank which
supplies water and a fertilizer to the tray. According to the
nutrient solution supplying device 14, whose specific arrangement
is not shown in the drawings, the tray in which the plants 40 are
provided is supplied with a culture solution which has been pumped
from the culture solution tank via an outward pipe, and the culture
solution supplied to the tray returns to the culture solution tank
via a return pipe. This enables nutriculture.
[0056] It is also possible to provide, for example, a water
purifying apparatus which purifies water contained in a culture
solution in the culture solution tank, and a fertilizer feeding
apparatus which supplies a fertilizer or the like to a culture
solution.
[0057] According to the plant cultivation device 1 of the present
embodiment, it is possible to set, for example, a room temperature,
a humidity, and an operating time by use of the operation panel
such that in the daytime, the temperature is set to 25.degree. C.,
the humidity is set to 60%, and the operating time is set to 16
hours, and in the nighttime, the temperature is set to 15.degree.
C., the humidity is set to 80%, and the operating time is set to 8
hours.
[0058] Note that the side wall 16 of the cultivation chamber 10 may
be provided with an observation window via which a state of the
inside of the cultivation chamber can be observed from the outside
of the cultivation chamber. From the viewpoint of an improvement in
pressure resistance and dew condensation prevention, it is
preferable that the observation window be a double window.
[0059] In order to allow the observation window to be more
resistant to pressure, it is more preferable that an inner part of
the double window be made of pressure-resistant glass.
Alternatively, in order to prevent dew condensation, it is also
possible to provide an inner surface of the observation window (the
cultivation chamber side surface of the observation window) with a
water repellent sheet and/or a wiper.
[0060] Subsequently, the sealed structure of the carry-in opening
30 is described below with reference to FIG. 1 to FIG. 3. FIG. 2 is
an exploded view of components of the sealed structure provided to
a surface of the wall surrounding the carry-in opening 30. FIG. 3
shows how to close the carry-in opening 30 with a cover 31 which is
provided to the side wall of the cultivation chamber 10.
[0061] The components of the sealed structure include the cover 31,
a packing (also referred to as a gasket) 32, a hinge 33, and a
swivel 34 (see FIG. 1 and FIG. 3).
[0062] The cover 31, which is hemispherical, is provided to a
surface of the wall surrounding the carry-in opening 30 so that a
hemispherical protrusion is formed on an inner surface of the side
wall 16 of the cultivation chamber 10 when the carry-in opening 30
is closed with the cover 31.
[0063] The packing 32 is embedded in a groove 36 formed on the
inner surface of the side wall 16. When the carry-in opening 30 is
closed with the cover 31, a surface 31a of the cover 31 is brought
into contact with the groove, and then the packing 32 is sandwiched
between the cover 31 and the side wall 16. This can prevent air
from leaking out from a gap between the carry-in opening 30 and the
cover 31.
[0064] The hinge 33 is provided to the inner surface of the side
wall 16 in a lower part of the carry-in opening 30. Specifically,
one side of the hinge 33 is connected to the inner surface of the
side wall 16, and the other side of the hinge 33 is connected to an
end of the cover 31 (see a circle A shown in FIG. 3 and drawn in a
dashed line). The cover 31 is connected to the side wall 16 via the
hinge 33, and the carry-in opening 30 is openable and closable by
moving the cover 31 in a direction as shown by an arrow in FIG.
3.
[0065] The swivel 34 (a second connecting member) is provided to
the inner surface of the side wall 16 in an upper part of the
carry-in opening 30. The swivel 34 is constituted by a first
protrusion 34a, a moving part 34b, and a second protrusion 34c. The
moving part 34b is connected to the second protrusion 34c with a
screw or the like, and is elastic. The moving part 34b is in
contact with the first protrusion 34a in a normal state (in a state
in which no external force is applied thereto). In a case where an
external force is applied to the moving part 34b, the moving part
34b, which is elastic, is pressed toward the side wall 16 assuming
that a point of connection with the second protrusion 34c is a
reference point.
[0066] In order to cause the carry-in opening 30 to be in a closed
state, it is possible to close the carry-in opening 30 with the
cover 31 by embedding, in the swivel 34 which has a structure as
described above, a protrusion 35 (first connecting member) which is
U-shaped and is provided to an inner surface of the cover 31 which
is hemispherical, into the is configured as above (i.e., by
pressing the moving 34b of the swivel 34 with the protrusion 35 and
causing the first protrusion 34a of the swivel 34 to be through the
aperture 35a of the protrusion 35a). The inner surface of the cover
31 means an inner surface of a hemisphere. However, this inner
surface, which faces the outside of the cultivation chamber, is
also referred to as an outer surface.
[0067] According to the arrangement, the cover 31 can be fixed
without fail with the carry-in opening 30 closed with the cover
31.
[0068] Note that a structure in which the swivel 34 and the
protrusion 35 are connected is an example of the present invention
and the present invention is not limited to the structure. It is
only necessary to arrange the present invention such that the cover
31 can be fixed to the side wall 16 by causing the first connecting
member provided to the cover 31 and the second connecting member
provided to the side wall 16 in a vicinity of the carry-in opening
30 to engage with each other.
[0069] Note that the hinge 33 is provided to the side wall 16 in
the lower part of the carry-in opening 30 and the swivel 34 is
provided to the side wall 16 in the upper part of the carry-in
opening 30 (see examples shown in FIG. 1 through FIG. 3). However,
the present invention is not limited to such an arrangement. For
example, the hinge 33 and the swivel 34 may be provided to the side
wall 16 in the upper part and the lower part, respectively, of the
side wall 16. Alternatively, the hinge 33 and the swivel 34 may be
provided to either one of the right side or the left side of the
carry-in opening. However, it is preferable that the hinge 33 and
the swivel 34 be provided so as to face each other with the
carry-in opening 30 therebetween. This enables the cover 31 to
easily open and close the carry-in opening 30.
[0070] The plant cultivation device 1 having the arrangement is
sealed, from the inside of the cultivation chamber 10 via the
packing 32, with the cover 31 which is hemispherical. Therefore, in
a case where an internal pressure of the cultivation chamber 10 is
increased by supplying compressed air from the oil free compressor
20, an internal and external pressure difference causes a force
toward an outside of the cultivation chamber to be applied to the
cover 31 which is hemispherical.
[0071] This causes a force to be applied to the cover 31 in a
direction in which the cover 31 is adhered to the side wall 16.
This force increases in proportion to the increase in internal
pressure. This allows an improvement in sealing property of the
carry-in opening 30. The packing 32 provided between the cover 31
and the side wall 16 also allows an improvement in sealing
property.
[0072] As described earlier, according to a structure of the plant
cultivation device 1 of the present embodiment, an increase in
external pressure (atmospheric pressure outside the cultivation
chamber 10) prevents obtainment of an improvement in sealing
property and pressure resistance, whereas the increase in internal
pressure (atmospheric pressure inside the cultivation chamber 10)
allows obtainment of a high sealing property and a high pressure
resistance. The plant cultivation device 1 has a door which has a
simpler structure than a door of a conventional sealed facility.
Therefore, the door of the plant cultivation device 1 can be
provided at a lower cost. The cultivation chamber 10 is provided
with not only the carry-in entrance 30 having the sealed structure
but also the inlet/outlet 11 which is connected to the oil-free
compressor 20 and serves as an opening to the outside for
ventilation. Meanwhile, a part of the cultivation chamber 10 which
part is obtained by excluding the carry-in entrance 30 and the
inlet/outlet 11 is a completely sealed space.
[0073] Therefore, the cultivation chamber 10 of the present
embodiment can be used as a sealed facility which is resistant to a
high pressure that is not more than approximately 10 atmospheres.
This allows achievement of plant cultivation in a high pressure
environment.
[0074] Note that according to the present embodiment, the cover 31
has a hemispherical shape. However, the present invention is not
limited to this.
[0075] Each of the sealed structure and the cover of the present
invention is required to have a structure which allows obtainment
of a high sealing property and a high pressure resistance in case
of the increase in internal pressure (pressure inside the
cultivation chamber 10). In order to create such a structure, it is
only necessary that the cover 31 which is closed (i) be in contact
with the inner surface of the side wall 16 of the cultivation
chamber 10 and (ii) have a shape protruding toward the inside of
the cultivation chamber 10.
[0076] According to this, in case of the increase in internal
pressure of the cultivation chamber 10, an internal and external
pressure difference causes a force toward the outside of the
cultivation chamber to be applied to the cover 31, so that a
sealing property can improve. The cover 31 which has a shape
protruding toward the inside of the cultivation chamber 10 allows a
great force caused by the internal pressure of the cultivation 10
to be directed toward the outside of the cultivation chamber 10 on
a surface of the cover 31.
[0077] Note that it is preferable that the cover 31 have a
hemispherical shape from the viewpoint of obtainment of an effect
of allowing a pressure to be applied equally to the surface of the
cover 31.
[0078] The plant cultivation device 1 of the embodiment of the
present invention assumes that plant cultivation is carried out in
an environment whose pressure is much higher than an outdoor air
pressure. Therefore, the plant cultivation device 1 is provided
with no system for carrying out ventilation in the cultivation
chamber 10. Therefore, in a case where ventilation needs to be
carried out, ventilation is carried out in the cultivation chamber
10 by opening the carry-in opening 30 after stopping an application
of a pressure by the oil compressor 20.
[0079] Subsequently, a plant cultivation method of the present
invention is described below. The plant cultivation method of the
present invention is a method for cultivating a plant by using, for
example, the plant cultivation device 1 in high pressure
environment which is impossible in a natural environment (e.g., has
a pressure of not less than 2 atmospheres).
[0080] The inventors of the present invention cultivated a plant
under a high pressure condition as shown in Example described
later. Then, the inventors obtained a result such that plant growth
was further promoted in a high pressure environment having a
pressure of more than 1 atmosphere to 4 atmospheres than in an
environment having a normal pressure (approximately 1
atmosphere).
[0081] Namely, according to the plant cultivation method of the
present invention, plant growth is promoted by cultivating a plant
in a high pressure environment having a pressure of not less than
1.5 atmospheres and not more than 10 atmospheres, preferably of not
less than 1.5 atmospheres and not more than 4 atmospheres, and more
preferably of not less than 2 atmospheres and not more than 3
atmospheres.
[0082] An example of the invention is described below.
EXAMPLE
[0083] According to the present example, an influence of an
atmospheric pressure on plant growth was examined under a condition
in which a plant cultivation facility capable of changing its
internal pressure was used and the internal pressure was variously
changed.
[0084] FIG. 4 shows an arrangement of a plant cultivation facility
used in the present example. FIG. 5 shows an external appearance of
the plant cultivation facility used in the present example.
[0085] A plant cultivation facility 50 mainly includes a
pressure-resistant container 51, a gas supply pipe 52 which
supplies compressed air to the pressure-resistant container 51, a
gas exhaust pipe 53 which exhausts air from the pressure-resistant
container 51, and a metal halide lamp 54 which emits light to an
inside of the pressure-resistant container 51 (see FIG. 4).
[0086] The pressure-resistant container 51 is mainly provided with
a culture solution storage 55 in which a culture solution for
cultivating a plant is stored, an observation window 56 via which
plant growth is observed from an outside, and a lighting window 57
via which light emitted from the metal halide lamp 54 is taken into
the pressure-resistant container 51. The observation window 56 and
the lighting window 57 are made of quartz glass.
[0087] According to the present example, two plant cultivation
facilities 50 (see FIG. 4 and FIG. 5) were used, and a condition in
which an internal pressure of one of the two plant cultivation
facilities 50 was maintained at a normal pressure (this condition
is referred to as a condition A), and a condition which was
identical to the condition A except that an internal pressure of
the other of the two plant cultivation facilities 50 was maintained
at 2 atmospheres (this condition is referred to as a condition
B).
[0088] Arabidopsis thaliana, which is designated as a standard
plant in a cultivation and gene research field, was cultivated
under each of the conditions A and B for two days.
[0089] Other conditions were a temperature of 13.degree. C. to
18.degree. C. and an illuminance of 80 .mu.mol/m.sup.2s (a bright
period: 16 hours, a dark period: 8 hours). Rock wool was used as a
culture medium (a base sheet shown in FIG. 6), a seedling of the
Arabidopsis thaliana which seedling was obtained approximately 14
days after germination was planted in the rock wool. Then, the
seedling was placed in a basin to be soaked in a
commercially-available Hyponex aqueous solution (produced by
HYPONeX JAPAN CORP., LTD.).
[0090] A result of this is shown in FIG. 6. As shown in FIG. 6, it
was found that plant growth was further promoted under the
condition B (shown on the right side of FIG. 6) than under the
condition A (shown on the left side of FIG. 6). Specifically, an
average leaf diameter of 1.25 cm was obtained under the condition
A, whereas an average leaf diameter of 1.37 cm was obtained under
the condition B. This reveals that plant growth was further
promoted under the condition B than under the condition A by
approximately 10%.
[0091] A graph of FIG. 7 shows the number (an average) of leaves of
each seedling obtained in a case where Arabidopsis thaliana is
grown under a condition which is identical to the condition A
except that the internal pressure of the plant cultivation facility
50 was set to 1, 2, 3, and 4 atmospheres. As shown in the graph, it
was found that the number of leaves was the highest at 2
atmospheres from 1 atmosphere to 4 atmospheres, the number
decreased in accordance with an increase in atmospheric pressure,
and leaves as many as those obtained at 1 atmosphere were obtained
at 4 atmospheres.
[0092] Note that no experiment of plant cultivation is carried out
between 1 atmosphere and 2 atmospheres, between 2 atmospheres and 3
atmospheres, and between 3 atmospheres and 4 atmospheres. However,
it is expected that a result similar to that shown in a dashed line
of FIG. 7 will be obtained.
[0093] According to the above results, it was confirmed that plant
cultivation under a condition at an atmospheric pressure which was
higher than a normal atmospheric pressure (approximately 1
atmosphere) (more preferably under a condition at an atmospheric
pressure from 1.5 atmospheres to 4 atmospheres) allowed promotion
of growth of a plant (especially a brassicaceous plant such as
Arabidopsis thaliana).
[0094] As described earlier, according to the plant cultivation
method of the present invention, a plant is cultivated in a high
pressure environment having a pressure of not less than 1.5
atmospheres and not more than 10 atmospheres. Note here that it was
determined in accordance with the graph shown in FIG. 7 that a
lower limit value of 1.5 atmospheres was an atmospheric pressure
that was more significantly capable of promoting plant growth than
a normal pressure (1 atmosphere). Note also that it was determined
that an upper limit value of 10 atmospheres was a physically
settable atmospheric pressure in terms of a function of a plant
cultivation device.
[0095] Note that according to the plant cultivation method of the
present invention, it is more preferable to cultivate a plant in a
high pressure environment having a pressure of not less than 1.5
atmospheres and not more than 4 atmospheres. According to this, it
is possible to, for example, easily set a pressure condition by
using the plant cultivation device of the present invention or the
like. It is also possible to further promote plant growth under a
condition at such a high pressure than under a condition at a
normal atmospheric pressure (see FIG. 7).
[0096] It is more preferable to cultivate a plant in a high
pressure environment having a pressure of not less than 2
atmospheres and not more than 3 atmospheres. According to this, the
average number of leaves is not less than 20 in the present
embodiment (see FIG. 7) and plant growth can be most promoted.
[0097] As described earlier, the plant cultivation method of the
present invention allows further promotion of plant growth than a
conventional plant cultivation method carried out at a normal
pressure. As proved especially by the results of the present
example, the plant cultivation method of the present invention
enables a reduction in seedling raising period. Since the reduction
in seedling raising period contributes to a cost reduction, the
present invention seems to be high in usefulness. Therefore, it is
preferable to apply the plant cultivation method of the present
invention to seedling raising carried out in a seedling raising
device or the like.
Embodiment 2
[0098] Next, a second embodiment of the present invention is
described below with reference to FIG. 8 through FIG. 9. First, the
present embodiment discusses another arrangement of a plant
cultivation device for achieving plant cultivation in a high
pressure environment.
[0099] FIG. 8 schematically shows an arrangement of a plant
cultivation device 61 in accordance with the another embodiment of
the present invention. The plant cultivation device 61 includes a
cultivation chamber 10 of a closed system and an oil-free
compressor 20 for causing an inside of the cultivation chamber 10
to be a high pressure environment (see FIG. 8). Note that members
of the plant cultivation device 61 of the present embodiment, the
members having arrangements identical to those of the respective
members of the plant cultivation device 1 shown in FIG. 1 are given
respective identical reference numerals.
[0100] The following description mainly discusses an arrangement
which is different from that of Embodiment 1.
[0101] According to the present embodiment, the oil-free compressor
20 is connected, via a pipe 72, to an inlet/outlet 71 which is
provided on a cover 31 for closing a carry-in opening 30. This
makes it possible to supply compressed air to the cultivation
chamber 10. A commonly used compressor can be used as the oil-free
compressor 20.
[0102] As described above, the present embodiment is different from
Embodiment 1 in that the inlet/outlet 71 is provided not on the
side wall 16 of the cultivation chamber 10 but on a part of the
cover 31. A description of the arrangements of the other members of
the present embodiment, to which arrangements the respective
arrangements of Embodiment 1 are applicable, is omitted here.
[0103] FIG. 9 shows an arrangement of (i) the cover 31 for closing
the carry-in opening 30 and (ii) the oil-free compressor 20 which
is connected to the inlet/outlet 71 provided on the cover 31. It is
not particularly limited in which part of the cover 31 to provide
the inlet/outlet 71. It is preferable that the inlet/outlet 71 be
provided so as to be comparatively close to a hinge 33 (see FIG.
9).
[0104] According to this, in a case where the carry-in opening 30
is opened with the cover 31 open, the inlet/outlet 71 which is
provided so as to be comparatively close to a hinge 33 can further
prevent the pipe 72 from interfering with carrying in and out of a
plant, a material, or the like as compared to the inlet/outlet 71
which is provided in a vicinity of a tip of the cover 31 which is
hemispherical.
[0105] Note that the pipe 72 is obtained by connecting two pipes: a
pipe 72b on the cover 31 side and a pipe 72a on the oil-free
compressor 20 side. An English valve 73 is provided on the pipe 72b
side, and a connecting part 74 which is connected with the English
valve 73 is provided on the pipe 72a side.
[0106] According to the arrangement, even in a case where the
oil-free compressor 20 once increased an internal pressure of the
cultivation chamber 10 and then the English valve 73 and the
connecting part 74 are disconnected by a function of the English
valve 73, it is possible to maintain the internal pressure. Also in
a case where a plant, a material, or the like is carried in and out
with the carry-in opening 30 open, a disconnection of the pipe 72
(72a and 72b) in a space between the connecting part 74 and the
English valve 73 makes it possible to prevent the pipe 72 from
interfering with the carrying in and out.
[0107] The plant cultivation device 61 having the arrangement is
sealed, from the inside of the cultivation chamber 10 via the
packing 32, with the cover 31 which is hemispherical. Therefore, in
a case where an internal pressure of the cultivation chamber 10 is
increased by supplying compressed air from the oil-free compressor
20, an internal and external pressure difference causes a force
toward an outside of the cultivation chamber to be applied to the
cover 31 which is hemispherical. This causes a force to be applied
to the cover 31 in a direction in which the cover 31 is adhered to
the side wall 16. This force increases in proportion to the
increase in internal pressure. This allows an improvement in
sealing property of the carry-in opening 30. The packing 32
provided between the cover 31 and the side wall 16 also allows an
improvement in sealing property.
[0108] As described earlier, according to a structure of the plant
cultivation device 61 of the present embodiment, an increase in
external pressure (atmospheric pressure outside the cultivation
chamber 10) prevents obtainment of an improvement in sealing
property and pressure resistance, whereas the increase in internal
pressure (atmospheric pressure inside the cultivation chamber 10)
allows obtainment of a high sealing property and a high pressure
resistance.
[0109] Therefore, the cultivation chamber 10 of the present
embodiment can be used as a sealed facility which is resistant to a
high pressure that is not more than approximately 10 atmospheres.
This allows achievement of plant cultivation in a high pressure
environment.
[0110] According to the present embodiment, the inlet/outlet 71 is
provided in the cover 31, and the cultivation 10 has no vent hole
other than the carry-in opening 30. That is, it is possible to
create a high pressure environment by providing, to a conventional
closed facility, one (1) structure which can serve as both a
carry-in opening and an inlet/outlet. Therefore, in a case where a
conventional facility is renovated to obtain a plant cultivation
device of the present invention, the arrangement of the present
embodiment allows a further reduction in cost for the renovation as
compared to the arrangement of Embodiment 1.
[0111] Note that the plant cultivation method of the present
invention (described earlier) can be carried out by use of the
plant cultivation device 61 of the present invention. It is only
necessary that the cultivation chamber 10 be set to have an
internal pressure of not less than 1.5 atmospheres and not more
than 10 atmospheres, preferably of not less than 1.5 atmospheres
and not more than 4 atmospheres, and more preferably of not less
than 2 atmospheres and not more than 3 atmospheres. Plant
cultivation in such a high pressure environment enables plant
growth.
[0112] The present invention is not limited to the description of
embodiments above, but may be altered by a skilled person within
the scope of the claims. An embodiment based on a proper
combination of technical means disclosed in different embodiments
is encompassed in the technical scope of the present invention.
[0113] As described earlier, a plant cultivation method in
accordance with the present invention includes the steps of:
placing a plant under a condition at a pressure of not less than
1.5 atmospheres and not more than 10 atmospheres; and cultivating
the plant.
[0114] The method enables further promotion of plant growth as
compared to a method of cultivating a plant at a normal pressure
(approximately 1 atmosphere).
[0115] The plant cultivation method of the present invention is
preferably arranged such that the plant is placed under a condition
at a pressure of not less than 1.5 atmospheres and not more than 4
atmospheres.
[0116] According to the method, it is possible to easily set up a
pressure condition by using, for example, a plant cultivation
device of the present invention. It is also possible to further
promote plant growth under such a condition than under a condition
at a normal atmospheric pressure (see FIG. 7).
[0117] In order to attain the object, a plant cultivation device in
accordance with the present invention includes: a cultivation
chamber in which plant cultivation is carried out; a compressor
which supplies compressed air into the cultivation chamber; a
carry-in opening which is provided on a wall of the cultivation
chamber and via which a material is carried in/out to/from the
cultivation chamber; and a cover which is provided to the carry-in
opening and has a shape that protrudes toward an inside of the
cultivation chamber, the cover closing the carry-in opening by
being in contact with a surface of the wall surrounding the
carry-in opening, the surface being located on the cultivation
chamber side, and the cultivation chamber having an internal
pressure higher than an atmospheric pressure by causing the
compressor to supply compressed air into the cultivation chamber in
a state in which the carry-in opening is closed.
[0118] A plant cultivation device of the present invention includes
a cultivation chamber and a compressor which supplies compressed
air into the cultivation chamber. The plant cultivation device
causes the cultivation chamber to have an internal pressure higher
than an atmospheric pressure by causing the compressor to supply
compressed air in a state in which a carry-in opening provided to
the cultivation chamber is closed with a cover.
[0119] According to such a plant cultivation device, the cover
provided to the carry-in opening closes the carry-in opening by
being in contact with a surface (i.e., an inner surface) of a wall
surrounding the carry-in opening, the surface being located on the
cultivation chamber side. In other words, the cover is arranged to
cover the carry-in opening from the inside of the cultivation
chamber. Note here that, in a case where the internal pressure of
the cultivation chamber is increased by supplying compressed air
into the cultivation chamber from the compressor, an internal and
external pressure difference causes a force toward an outside of
the cultivation chamber to be applied to the cover. According to
the arrangement in which the cover covers the side wall surrounding
the carry-in opening from the inside of the cultivation chamber,
the force is applied to the cover in a direction in which the cover
is adhered to a side wall of the cultivation chamber. Thus, the
arrangement enables an improvement in sealing property of the
cultivation chamber. Further, the arrangement prevents the cover
from coming off also in a case where the internal pressure of the
cultivation chamber rises. This allows a vicinity of the carry-in
opening to be more resistant to pressure.
[0120] In addition, the cover which has a shape that protrudes
toward the inside of the cultivation chamber allows an increase in
surface area of the cover. According to this, a large force which
is caused by the internal pressure of the cultivation chamber 10 is
applied, toward the outside of the cultivation chamber, to a
surface of the cover which surface faces the cultivation chamber.
Thus, the arrangement allows a further improvement in sealing
property in accordance with an increase in internal pressure of the
cultivation chamber.
[0121] As described earlier, the plant cultivation device of the
present invention makes it possible to cultivate a plant while
maintaining an internal pressure of the cultivation chamber so that
the internal pressure is higher than an atmospheric pressure.
[0122] Note that it is preferable that the cover have a protrusion
having a curved surface. This prevents a pressure from being
applied to the surface of the cover nonuniformly. Note here that
the curved surface is exemplified by a hemispherical surface, a
paraboloidal surface, a semielliptical surface, and a hyperboloidal
surface.
[0123] The plant cultivation device of the present invention is
preferably arranged such that the shape of the cover is
hemispherical.
[0124] According to the arrangement, a pressure can be applied
equally to the curved surface of the shape which is
hemispherical.
[0125] The plant cultivation device of the present invention is
preferably arranged to further include: a hinge which is provided
to the surface of the wall of the cultivation chamber, the surface
being located on the cultivation chamber side, the cover being
connected via the hinge to the wall of the cultivation chamber.
[0126] The arrangement allows the cover to be constantly connected
to the wall of the cultivation chamber. The arrangement also allows
the carry-in opening to be opened and closed by moving the cover in
accordance with a movement of the hinge.
[0127] The plant cultivation device of the present invention is
preferably arranged to further include: a first connecting member
which is provided on an outer surface of the cover; and a second
connecting member which is provided on the wall of the cultivation
chamber, the first connecting member and the second connecting
member engaging with each other in a state in which the carry-in
opening is closed with the cover.
[0128] Note here that the outer surface of the cover refers to a
surface which is located outside the cultivation chamber in a state
in which the carry-in opening is closed. According to the
arrangement, it is possible to fix the cover in a state in which
the carry-in opening is closed with the cover.
[0129] The plant cultivation device of the present invention is
preferably arranged to further include: a packing which is provided
between the cover and the wall of the cultivation chamber, the
carry-in opening being closed in a state in which the packing is
sandwiched between the cover and the wall surrounding the carry-in
opening.
[0130] According to the arrangement, the packing which is
sandwiched between the cover and the wall surrounding the carry-in
opening allows securer prevention of a leak of air from a gap
between the carry-in opening and the cover.
[0131] The plant cultivation device of the present invention is
preferably arranged to further include: an inlet/outlet which is
provided to the cover, the compressor supplying compressed air into
the cultivation chamber via the inlet/outlet.
[0132] According to the arrangement, the carry-in opening and the
inlet/outlet are provided together in one (1) place. This makes it
possible to easily create a high pressure environment by providing,
to a conventional closed facility, one (1) structure which can
serve as both the carry-in opening and the inlet/outlet.
[0133] In order to attain the object, a plant cultivation method
for carrying out cultivation by use of a plant cultivation device
mentioned above, the method includes the steps of: placing a plant
under a condition at a pressure which is higher than an atmospheric
pressure; and cultivating the plant.
[0134] The method makes it possible to easily set a condition at a
pressure which is higher than an atmospheric pressure. The method
also allows further promotion of plant growth as compared to a
plant cultivation method carried out at a normal pressure
(approximately 1 atmosphere).
[0135] The plant cultivation method of the present invention is
preferably arranged such that the plant is placed under a condition
at a pressure of not less than 1.5 atmospheres and not more than 4
atmospheres.
[0136] According to the method, it is possible to further promote
plant growth under such a condition than a condition at a normal
atmospheric pressure.
[0137] As described earlier, the plant cultivation method in
accordance with the present invention is a method for carrying out
plant cultivation in a cultivation chamber for plant cultivation,
the cultivation chamber being a sealed space in which a plant is
placed, the method including the step of: cultivating the plant by
causing a pressure device to increase an internal pressure of the
cultivation chamber so that the internal pressure is higher than an
atmospheric pressure.
[0138] The method allows further promotion of plant growth as
compared to a plant cultivation method carried out at an
atmospheric pressure (approximately 1 atmosphere).
INDUSTRIAL APPLICABILITY
[0139] Plant cultivation in a high pressure environment is
accomplished by use of a plant cultivation device of the present
invention. Accordingly, the plant cultivation device of the present
invention is applicable to a plant cultivation method of the
present invention. The plant cultivation method of the present
invention makes it possible to promote plant growth.
REFERENCE SIGNS LIST
[0140] 1 Plant cultivation device [0141] 10 Cultivation chamber
[0142] 11 Inlet/outlet [0143] 12 Lighting apparatus [0144] 13
Temperature and humidity sensor [0145] 14 Nutrient solution
supplying device [0146] 15 Temperature and humidity control device
[0147] 16 Side wall (Wall) [0148] 20 Oil-free compressor
(Compressor, Pressure device) [0149] 21 Pipe [0150] 30 Carry-in
opening [0151] 31 Cover [0152] 32 Packing [0153] 34 Swivel (Second
connecting member) [0154] 35 Protrusion (First connecting member)
[0155] 61 Plant cultivation device [0156] 71 Inlet/outlet [0157] 72
Pipe
* * * * *
References